When a lamp provided with a projection lens is attached to a housing which defines a lamp chamber, an error may occur in a required specification with respect to a reference position of an optical axis of the projection lens. In order to solve the error, there has been known a lamp provided with an aiming mechanism.
The aiming mechanism includes two screws exposed to an outside of a housing. For example, Japanese Patent Laid-Open Publication 2012-43656 discloses an aiming mechanism in which a reference position of an optical axis related to a vertical direction of a lamp is adjusted by rotating one screw, and a reference position of an optical axis related to a horizontal direction of the lamp is adjusted by rotating the other screw.